沥青浸渍炭化C/C复合材料密度及孔隙分布

Distribution of Density and Pores of C / C Composite Prepared by Pitch Impregnation and Carbonization

文摘以径棒法编织成型预制体,采用沥青浸渍炭化工艺制备了C/C复合材料(1.50 g/cm3),采用CT检测了试件的密度分布特征,并采用光学显微镜和压汞法分析了试件的孔隙分布特征。结果表明,在沥青浸渍炭化的工艺条件下,试件外端密度最高,由外端到中心沿径向密度递减;以坯体中心为参照点,同一圆周方向密度均匀分布;坯体开孔率沿径向由外端到中心递增;坯体大孔和中孔孔容积比率沿径向从外端到中心递增,而微孔孔容积比率则从外端到中心递减。

By taking preform weaven with radial carbon rods as reinforcement phase, C/C composite was pre- pared by impregnation and carbonization process using coal tar pitch as matrix precursor, and its bulk density is 1.50 g/cm3. The distribution of density was tested by CT, and the distribution of pores were analyzed by means of optical microscope and mercury intrusion method. The results showed that the density of outer fringe of body is the highest, and the density decreased from outboard to center along radial of the body under the technological conditions of pitch impregnation and carbonization. The density distributed evenly along the direction of identical circle taking body cen- ter as reference point. The porosity of the body increased from outboard to center along radial of the body. The pore volume ratio of macropores and mesopores increased from outboard to center along radial of the body, on the contrary, the pore volume ratio of micropores decreased from outboard to center along radial of the body .